Recently, color images have been increasingly utilized with color liquid crystal displays and the like, and a demand for higher image quality has been increased. Color filters are indispensable to color displays in the liquid crystal display, and an important part that governs the performance of the liquid crystal display. As a method for producing a color filter in the related art, a dyeing method, a printing method, an inkjet method, a photoresist method, and the like are known. Among these, the photoresist method is the mainstream of the production method of these days because spectral characteristics and reproductivity can be easily controlled, and high resolution enables highly fine patterning.
The photoresist method usually uses pigments as a coloring agent. Unfortunately, it is known that the pigment has a fixed particle size, and has depolarization action (a phenomenon that polarization is destroyed), reducing the contrast ratio in color display in the liquid crystal display. Moreover, a system using the pigment has difficulties in providing high transmittance of backlight, and has limitation in improving the lightness of the color filter. Further, the pigment is insoluble in organic solvents and polymers. Accordingly, a colored resist composition can be obtained as a dispersed product, but the dispersion is difficult to stabilize. Contrary to this, dyes are usually soluble in organic solvents and polymers, and do not aggregate in the colored resist composition and are stable. For this reason, in a color filter obtained from a resist composition using a dye as the coloring agent, the dye is dispersed at a molecular level and has no depolarization action. Moreover, the dye has high transmittance of the backlight. In order to provide high spectral characteristics and enable image display with high display contrast, a red color filter using a monoazo dye C.I. Acid Red 6 has been reported (see Patent Literature 1). As broadband communications are increased, development of a color filter having good spectral characteristics and high lightness and chroma to attain a high contrast ratio has been increasingly demanded in order to display highly finer images.
Meanwhile, a thermal transfer recording method is a recording method in which, a thermal transfer sheet having a coloring material layer containing a heat transferable dye and an image receiving sheet having a dye receiving layer on the surface thereof are layered on a sheet-like substrate, and recording is performed by heating the thermal transfer sheet to transfer the dye in the thermal transfer sheet onto the image receiving sheet. In the thermal transfer recording method, the transfer sheet and the dye used in an ink composition for a transfer sheet are very important because these give great influences to the transfer recording speed, image quality of a recorded product, storage stability, and the like. As a dye used in such a thermal transfer recording method, an example using an anthraquinone dye has been reported (see Patent Literature 2).
However, development of a dye having high lightness and chroma and having sharpness and color reproductivity has been demanded.